COVID-19 is still a major issue, and many people are suffering from its long-term effects, known as long COVID. Scientists are working hard to understand the cause of long COVID and develop treatments. One area of progress has been made in epigenetics, specifically DNA methylation. A research group in Sweden has studied the DNA methylation of blood cells in patients with long COVID and found several genes and groups of genes with changes in their methylation after infection. These included genes involved in regulating ACE2, the protein the virus uses to invade cells, and genes involved in histamine signaling. This research could lead to better diagnosis and treatment of long COVID. Intriguingly, some of the methylated genes identified in a small Swedish study of 10 long COVID patients were related to taste and smell, two of the virus’ signature symptoms. Another US-based research group looked at 102 patients recovering from COVID in two papers published between 2021 and 2022, and found changes in DNA methylation that persisted after infection, although in different genes than the Swedish study. However, not all studies have supported a connection between methylation and long COVID, with a third study finding no difference in methylation between those with long COVID and those in remission.
Despite the small sample sizes, the genes identified in these studies could be relevant to long COVID if larger studies can validate their involvement. For example, the US-based group found that the pattern of gene expression could explain an increase in cardiovascular events following COVID-19, while the Swedish group identified genes related to ACE2, and even some similar self-antibodies to those seen in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (MECFS).
More research is needed to understand the link between long COVID and epigenetic changes, but it is clear that it is worth learning more about this virus and its effects. This video was made possible thanks to our supporters on Patreon, who not only make these videos possible but also get access to exclusive content and perks. To join the community of SciShow patrons, head to patreon.com/scishow to learn more. Thanks for watching!